Striatal dopamine mediates the interface between motivational and cognitive
control in humans: Evidence from genetic imaging
Esther Aarts, Ardi Roelofs, Barbara Franke, Mark Rijpkema, Guillén Fernández, Rick C.
Helmich, Roshan Cools
Correspondence should be addressed to Esther Aarts, Donders Institute for Brain, Cognition
and Behaviour, Radboud University Nijmegen, The Netherlands. Email address:
Initially, 24 participants were scanned. One participant was excluded due to technical
problems during scanning, one participant's saliva sample was not collected, genotyping of one
participant's saliva sample failed, and one participant had a DAT1 allele different from the two
alleles we were interested in. The remaining sample size was 20.
The targets of the Stroop-like task-switch paradigm consisted of written words in arrows.
The lines and letters of the targets were white on a black background (Figure 1, main text).